BRAINCAKEEnergy – forces doing work
Revision notes for Energy – forces doing work in Edexcel Physics (1PH0). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- Changes in the way energy is storedA system is an object or a group of objects.
- Energy transfer diagramsAn energy transfer diagram shows where energy goes in a change.
- Conservation of energy in a closed systemA closed system is a system where no energy enters or leaves.
- Ways of changing the energy of a systemThe energy of a system can be changed in three ways: by work done by forces, by work done in electrical equipment, and by heating.
- Measuring work done by a forceWhen a force moves an object, the force does work.
- Work done = force x distanceThe work done by a force is found using the equation: work done (J) = force (N) × distance moved in the direction of the force (m) In symbols, E = F…
- Energy changes when a system is changed by work done by forcesWhen a force moves an object, the force does work.
- Change in gravitational potential energyAn object raised above the ground gains energy in its gravitational potential energy store.
- Kinetic energyAny moving object has energy in its kinetic energy store.
- Energy dissipation in system changesEnergy is never created or destroyed, so the total energy stays the same in any system change.
- Wasteful mechanical processesIn a mechanical process, parts move against each other or through the air.
- Power as the rate of energy transferPower is the rate at which energy is transferred.
- Power, work done and time takenPower tells you how quickly energy is transferred, or how quickly work is done.
- The watt as joules per secondOne watt is a power of one joule per second.
- EfficiencyNo device transfers all of its input energy usefully.